package com.lky.reggie.controller;

import com.lky.reggie.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.web.bind.annotation.GetMapping;
import org.springframework.web.bind.annotation.PostMapping;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.multipart.MultipartFile;

import javax.servlet.ServletOutputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.util.UUID;

/**
 * @author shkstart
 * @Description
 * @date 2023-01-05-23:24
 */
@RestController
@Slf4j
@RequestMapping("/common")
public class FileController {

    @Value("${reggie.path}")
    private String basePath;

    /**
     * 文件上传
     * @param file
     * @return
     */
    @PostMapping("/upload")
    public R<String> upload(MultipartFile file)
    {
        //filr是一个临时文件，需要转存到指定的位置，否则本次请求完成后临时文件会被删除
        log.info(file.toString());

        //原始文件名
        String originalFilename = file.getOriginalFilename();
        String suffix = originalFilename.substring(originalFilename.lastIndexOf("."));
        //使用UUID重新生成文件名，防止文件名重复造成覆盖
        String fileName = UUID.randomUUID().toString()+suffix;

//创建一个目录对象
        File file1 = new File(basePath);
        //判断目录是否存在
        if(!file1.exists())
        {
            //目录不存在，才创建
            file1.mkdirs();
        }
        try {
            //保存到指定位置
            file.transferTo(new File(basePath+fileName));
        } catch (Exception e) {
            e.printStackTrace();
        } finally {
        }
        return R.success(fileName);
    }

    /**
     * 文件下载
     * @param name
     * @param response
     */
    @GetMapping("/download")
    public void download(String name, HttpServletResponse response)
    {
        FileInputStream fileInputStream=null;
        ServletOutputStream outputStream=null;

        //输入流，通过输入流读取文件内容
        try {
             fileInputStream = new FileInputStream(new File(basePath+name));

            //输出流，通过输出流将文件写回浏览器，在浏览器展示图片
             outputStream = response.getOutputStream();
            response.setContentType("image/jpeg");

            byte[] bytes=new byte[1024];
            int len=0;

            while((len=fileInputStream.read(bytes))!=-1)
            {
                outputStream.write(bytes,0,len);
                outputStream.flush();


            }

        } catch (FileNotFoundException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }finally {
            //关闭资源
            try {
                if(outputStream!=null) {
                    outputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
            try {
                if (fileInputStream!=null) {
                    fileInputStream.close();
                }
            } catch (IOException e) {
                e.printStackTrace();
            }
        }


    }
}
